This invention generally relates to the field of electromechanical sensing devices and more particularly to a device and method for sensing coughs emanating from the human body.
In recent years increased concern with consumer interest and corresponding governmental activity principally promulgated in the rules and regulations of the Food and Drug Administration and the Federal Trade Commission have made it desirable, if not mandatory, for suppliers of products, particularly those relating to or having affect on body function, to determine efficacy. One group of products undergoing close scrutiny are those preparations intended for the amelioration or decrease in frequency of the human cough. In conducting tests and studies in this area it immediately became evident to researchers that no accurate, dependable, and relatively portable device existed for sensing coughs.
Prior art devices while inherently capable of sensing and measuring coughs have proven incapable of discerning coughs from those other body functions which produce similar body manifestations. In sensing human coughs it is necessary that the device be able to determine or distinguish normal breathing and body movement therefrom.
A number of prior art patents which deal generally with the sensing and determination of body functions are: U.S. Pat. Nos. 1,619,005; 3,154,066; 3,727,606; 3,760,794; 3,782,368. All fail in one mode or other to either teach or suggest a body function monitor capable of sensing and recording human coughs with sufficient accuracy to permit use in tests of product efficacy. The most pertinent of these prior art patents is considered to be Pat. No. 3,154,066 entitled "Body Function Sensors" issued to Grindheim et al. on Oct. 27, 1964.
The instrument of this patent utilizes mechanical movement of a sensing member to alter the electrical characteristics of a strain gauge and thereby produce an electrical signal corresponding to the body function in question. The patent teaches the use of this device for the measurement of breathing and pulse rates. While in some limited mechanical details the device is similar to that of the present invention it has certain requisites that not only make it inapplicable to the sensing of coughs but inherently render it incapable thereof. In operation it is required that the device of this prior art patent be in some fashion or other snugly although not too tightly secured to the body in such a manner that the housing of the device is rendered substantially immovable by resting on skeletal structure of the body. This arrangement prevents the device from distinguishing body contortions or the act of breathing from a human cough, since both of these body functions as well as most others produce relative movement of tissue with respect to the skeletal frame.
To overcome problems associated with the prior art and to permit testing of product efficacy, it is the object of the present invention to provide a new and improved cough sensing device. It is a further object of the present invention to produce a cough sensor relatively insensitive to other body functions. It is another object of the present invention to produce a reliable and economical cough sensing device. It is yet another object of the invention to produce a cough sensor capable of transmitting signals to remotely located recording equipment. It is still another object of the present invention to provide a cough sensor capable of being comfortably carried and worn by the patient for extended periods.